The Financial Post reports in its Saturday, Aug. 31, edition that a recent proposal to tax the unrealized gains of wealthy Americans has sparked anger among some of Silicon Valley's wealthiest investors. A Financial Times dispatch to the Post reports that United States Vice-President Kamala Harris unveiled a tax plan last week with the aim of generating nearly $5-trillion (U.S.) over a decade. The plan includes support for a controversial tax proposal, which was also part of President Joe Biden's federal budget plan for 2025. Under the plan, individuals with more than $100-million (U.S.) in wealth would be required to pay taxes of at least 25 per cent on a combination of income and unrealized capital gains. Although it is considered a long shot on the political front, if enacted, this proposal would signify a fundamental change in how America's wealthiest individuals are taxed, as it would include investment gains before an asset is sold or when the individual passes away. This means that individuals such as Elon Musk, Warren Buffett and Jeff Bezos, whose wealth is largely derived from the stocks they own, as well as the founders and backers of successful start-up companies, would likely face significant tax bills.